Geographic Variation in Peromyscus leucopus Population Size and Small Mammal Community Richness in Northern...

The white-footed mouse, Peromyscus leucopus, is a generalist species found throughout the eastern and central United States that serves as an important reservoir for many tick-borne pathogens relevant to human health. Patterns of P. leucopus relative abundance within small mammal communities have been shown to correlate with the prevalence of Borrelia burgdorferi, the main causative agent of Lyme disease, in vector species. However, efforts to investigate patterns of P. leucopus population size and small mammal community structure often lack geographic variation. In this study, we characterized patterns of P. leucopus population size and small mammal community species richness across a broad geographic range in Pennsylvania. Population sizes and small mammal community richness values in northeastern Pennsylvania (mean $\hat{N}$  = 28.6; mean richness = 5.3) were greater than those in northwestern Pennsylvania (mean $\hat{N}$  = 19.7; mean richness = 2.8). Projected changes in climate and the expansion of human-caused disturbance have the potential to greatly influence the prevalence of P. leucopus in small mammal communities, so regular characterizations of P. leucopus community dynamics will likely be helpful to inform projections and assessments of human exposure to tick-borne pathogen risk.